In my opinion a new question should be asked, with a correct answer, and the Old question, with the Incorrect answer should be tagged as the dupe of the NEW question.
this seems to have been done before https://scifi.meta.stackexchange.com/a/6601/29220
as alex says
Just because two questions are duplicates doesn't mean we have to close the new question as a dupe of the old one. We make the question with the best answers the "canonical" question, and closes others as a dupe of that, regardless of the order in which they were posted.
again common consensus seems to be,
https://scifi.meta.stackexchange.com/a/4746/29220
Izkata says,
No. In general, choose the better one to keep open, as long as it is significantly better.
Beofett argues,
If they are essentially the same, the one with the better answers should be left open, and the other closed as a duplicate. This usually, but not always, results in the older version being left open.